The symptoms of driving under the influence of alcohol begin with rash driving. This initial give-away or the routine DUI stops are followed by simple or detailed tests to check your sobriety. The National Highway Traffic and Safety Administration (NHTSA) guidelines were set up to engage the driver in standardized field sobriety tests. Other than these, there are also non-standard tests.

It’s more common in most of the states to detain drivers suspected of DUI after conducting chemical tests of breath, blood or urine. Though voluntary, refusing to undertake these tests may result in suspension of driving privileges. The simplest test that could be done by the road-side itself involves the breathalyzer, a hand-held device, that measures blood alcohol concentration levels in the driver’s body.

Standardized Tests

One-Leg Stand Test: This is a reliable (about 65 percent) test to check whether the driver is drunk. In this test, the driver is asked by the officer to stand with one foot raised to about 6 inches and count while standing. Start and stop when asked by the officer.

Walk and Turn Test: Combined with the one-leg stand, these tests clock up to 80 percent accuracy in indicating sobriety. The test requires the driver to walk heel-to-toes nine steps, turn, and walk back. As always, the driver must be able to understand the instructions and follow them.

Horizontal Gaze Nystagmus: Similarly reliable is this test where the police officer guides a penlight in front of the driver’s eyes asking the driver to follow the pen using his eyes. If the eyes twitch at less than 45 degrees, it can be counted as a sign for high blood alcohol level. Nystagmus is an involuntary twitching of the eye muscles when looking sharply to the sides.

Non-Standardized Tests

Rhomberg Balance Test: These tests are usually an officer’s prerogative. The Rhomberg test requires the driver to stand with the feet together and look up at the sky, leaning back. The arms should be held out to the sides while looking up and so, will be able to ascertain the driver’s balance.

Finger-to-Nose Test: A simple test requiring the drive to touch the tip of his nose while keeping his eyes closed.

Finger-Count Test: The driver simply has to count the raised fingers on the officer’s hand.

Hand Pat Test: In this test, the officer asks the driver to extend a hand with the palm upwards and place the other hand on it with the palm downwards. Then, the driver is required to pat the lower hand by rotating the upper hand so that the first pat is between the lower hand and the palm of the upper hand while the second pat is with the back of the upper hand. Repeat until requested by the officer.

ABC test: The driver is asked to recite the alphabets or a portion of it.

Numbers Backward Test: The officer will say a number and ask the driver to count backwards.

Both the tests, standard and non standard, seek to assure the police officer that the driver is capable of understanding simple instructions and following them upon request. The three standard ones are used most often when detaining someone suspected of driving under the influence of alcohol. Remember, contact an experience DUI/DWI attorney to understand specifics about field sobriety tests.